1. Field of the Invention
The present invention relates generally to an armature of a linear motor and, more particularly, to an armature of a linear motor that can be manufactured with improved production efficiency, the armature having a reduced weight and producing an increased thrust per weight.
2. Description of the Background Art
A linear motor includes as its principal parts an armature (moving part) and a stator which are disposed face to face with a specific magnetic gap formed in between. The armature includes a plurality of magnetic teeth arranged side by side in a linear form with coils wound around the individual magnetic teeth, each of the magnetic teeth having a laminated armature core block formed by laminating multiple tooth elements made of electromagnetic steel sheets. The stator includes a yoke and a plurality of magnets disposed face to face with the magnetic teeth of the armature separated by the aforementioned magnetic gap from each other.
To wind the coils at high density, an entire armature core is divided into multiple core blocks constituting the magnetic teeth and the coils are wound on the individual magnetic teeth. The armature is formed by assembling the magnetic teeth into a single structure by means of a mounting plate.
Each of the magnetic teeth has a dovetail groove formed in a surface opposite to a surface facing the stator. On the other hand, the mounting plate has projecting mating portions which fit into the dovetail grooves formed in the individual magnetic teeth. The magnetic teeth are assembled together by fitting the projecting mating portions of the mounting plate into the dovetail grooves as disclosed in Japanese Laid-open Patent Publication No. 2000-217334, for example.
The aforementioned construction of the conventional armature formed by assembling a plurality of magnetic teeth into a single structure has a problem in that the mating portions of the mounting plate must be fitted one by one into the dovetail grooves in the individual magnetic teeth and this results in low productivity.
Another problem of the conventional armature is that the aforementioned construction requires the dedicated mounting plate for joining together the individual magnetic teeth, the provision of the mounting plate resulting in an increase in weight and a reduction in thrust per weight ratings of the armature.